Section 10: Special Shunting Signals and Indicators

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As well as the ordinary shunting signals covered in Section 3 of this website, special shunting signals or indicators were developed for specific purposes such as hump shunting, propelling or loading/unloading. In some cases, standard signal types were used but with special meanings applied to their indications.

At some goods sidings, especially those where private locomotives worked, a signal was provided to intimate that all shunting must cease, to allow a train to enter the sidings from the main line unhindered. On the Midland Railway, this signal took the form of a centrally pivoted crossbar, painted red on both sides. When the crossbar was visible (or a red light shown at night) [10.1], all shunting had to stop. When shunting was allowed, the crossbar was turned edge on and a green light was shown at night [10.2]. On the North Eastern Railway, a board signal was used for the same purpose. The sides of the board were notched [10.3] to indicate that it applied only to sidings. These boards were nicknamed 'cotton bobbins' because of their shape. When shunting was allowed, the board was turned edge on, similar to the crossbar signal [10.2].

'Stop shunting' signals also existed in semaphore form. On the Great Eastern Railway, the signal had the words "stop shunt" written on the arm [10.4]. When the arm was lowered to the 'off' position [10.5], shunting was permitted.

The North Eastern Railway had an extraordinary form of shunting signal with a semaphore arm that operated in four positions. The signal was operated by a shunter. When the arm was in the horizontal position [10.6], the meaning was "stop". The arm was raised through 45° from horizontal [10.7] for "forward" or lowered through 45° [10.8] for "backover" (i.e. set back). When the signal was not in use, the arm was hidden inside a slot in the post and the light was obscured.

In 1929, the LNER opened Britain's first mechanised marshalling yard at Whitemoor. Wagons were propelled from reception sidings over a hump and, moving along by gravity, were sorted into the various sorting sidings. Signals at the hump summit indicated to drivers the speed at which wagons should be propelled over the hump. At Whitemoor Up Yard, a conventional four-aspect colour light signal was used for this purpose but with different meanings to drivers. A red aspect [10.9] carried the usual meaning, "stop". A single yellow aspect [10.10] meant "slow shunt", while a double yellow aspect [10.11] meant "quicker shunt". A green aspect [10.12] instructed the driver to "go forward smartly".

The mechanisation of Toton Down Yard by the LMS in 1939 introduced a new design of hump signal in position light form. Accordingly, these became known as 'Toton' signals. The indications "stop humping" [10.13], "hump slow" [10.14] and "hump normal" [10.15] were given by a line of white lights inclined at different angles. The signals were only illuminated while a humping movement was being made. A series of additional hump signals was installed along each of the arrival lines to govern moves towards the hump and these were located in such a way that the driver always had a clear view of at least one of them.

In the 1940s, the colour light hump signals at Whitemoor Up Yard (see [10.9 - 10.12]) were replaced by three-position upper quadrant semaphore signals. These were of the same type normally used as a main signal (see [2.76 & 2.77]) but their indications gave different meanings to drivers. The arm being in the horizontal position [10.16] carried the usual meaning, "stop". The arm raised through 45° from horizontal [10.17] was an instruction to drivers to propel towards the hump at normal speed, and through 90° [10.18] meant "approach hump smartly". A similar semaphore hump signal was provided at Ripple Lane in 1961.

Toton signals (see [10.13 - 10.15]) were provided as hump signals at most of the new mechanised marshalling yards that were brought into service during the 1950s and 1960s under the British Railways "Modernisation Plan" to handle large volumes of freight traffic. Some of these signals were double-sided. At Margam Yard, a form of cab signalling, which involved a three-position indicator fitted inside the locomotive cab, presented the driver with an indication comprising three white lights at an angle corresponding to the aspect shown by the lineside hump signal. Any change of indication was accompanied by an audible signal.

At many of the yards, a series of additional hump signals was installed along the reception sidings to govern moves towards the hump. Since only one train could be propelled over the hump at a time, these additional signals were designed to apply to either of the two sidings between which they were situated. For the "hump slow" indication, the diagonal white lights were displayed at opposite angles of inclination, depending on which siding the indication was applying to [10.19]. Wing application lights ("ears") were placed to the side of the hump signal [10.20 & 10.21]. Any aspect displayed was applicable to the siding on the same side as the illuminated application light. For consistency, a single application light was sometimes provided on a hump signal that applied to only one siding.

Some of the hump signals (usually those closest to the hump on each reception siding) had 'train engine release' signals placed underneath the main head. These signals were used to signal a locomotive that had finished propelling wagons towards the hump away from the reception sidings, usually via a line that bypassed the hump. On a hump signal that applied only to one siding, the engine release signal may be placed directly beneath the hump signal. The engine release signal usually took the form of a miniature two-aspect colour light signal, which was extinguished when the hump signal was illuminated. A red aspect [10.22] meant "stop" and a yellow aspect [10.23] meant "proceed as far as the line is clear towards the next signal". Some later engine release signals were in the form of a position light shunting signal (see [3.72] and [3.83]).

In the case of hump signals that applied to the lines on either side (see [10.20 & 10.21]), the application lights were not used in conjunction with the engine release signals. A separate engine release signal was positioned on each side of the signal post [10.24]. For consistency, the train engine release signal may be offset to the left or right on a hump signal that applied to only one siding.